New tool identifies high-risk lung patients: Ottawa COPD Risk Scale

February 18, 2014

A new clinical decision tool developed in Ottawa will help emergency physicians everywhere identify patients with chronic obstructive pulmonary disease (COPD) who are at risk of serious complications or death. The Ottawa COPD Risk Scale was published today in CMAJ (Canadian Medical Association Journal).

“We expect this risk scale, once fully validated, to be used widely in emergency departments to improve patient safety by identifying those who need to be admitted to hospital and those who could safely be sent home,” says Dr. Ian Stiell, emergency physician at The Ottawa Hospital, senior scientist at the Ottawa Hospital Research Institute and Chair of the University of Ottawa’s Department of Emergency Medicine. Dr. Stiell is world renowned for creating highly useful decision rules, such as the Ottawa Ankle Rules and Canadian C-Spine Rule.

Chronic obstructive pulmonary disease, usually caused by smoking, is a leading cause of hospitalization for seniors. In addition, more than one-third of people hospitalized for COPD end up at an emergency department within 30 days from discharge.

It can be challenging for emergency physicians to determine which patients with COPD should be admitted because, up until now, there has been little evidence to guide them about the risk factors for adverse events in patients with this condition. Adverse events include death within 30 days of visiting an emergency department, intubation or ventilation, heart attack and other serious events.

Researchers looked at data from 945 patients aged 50 years or older in six Canadian teaching hospitals (in Ottawa, Toronto, Kingston, Montreal, Quebec City and Edmonton) to determine characteristics associated with short-term adverse events. After analysing 20 clinical and laboratory predictors of risk, they developed the Ottawa COPD Risk Scale, a 10-point scale that includes elements from a patient’s history, examination or tests conducted during their visit.

The risk factors are easy to determine, do not need expensive testing and provide physicians with a quantitative estimate of risk for adverse events in COPD patients.

“We found that the risk of a serious adverse event varied from 2.2% for a score of 0, to 91.4% for a total score of 10,” says Dr. Ian Stiell, who also holds a University Health Research Chair from the University of Ottawa.

The researchers also found that 62% of COPD patients were being sent home from emergency departments in Canada, compared to 20% in the United States. They suggest that this is partly due to bed shortages and the resulting pressures for physicians to be sure that hospitalization is necessary.

“We are concerned by the number of serious adverse events among COPD patients discharged from the emergency department,” write Stiell and his co-authors. “Identification of high-risk characteristics by physicians has the potential to significantly improve patient safety by helping to ensure that patients most at risk for poor outcomes by admitted.”

They suggest the tool could also be used to identify patients who should have early follow up for COPD after discharge from hospital.

“Once validated, this scale will ultimately benefit both patients and health care systems by ensuring appropriate admissions, targeting those who need early follow-up, and diminishing unnecessary hospitalizations,” they conclude.

The tool was developed by researchers at the Ottawa Hospital Research Institute, the University of Ottawa Heart Institute, University of Ottawa, Ottawa, Ontario; University of Toronto, Toronto, Ontario; Queen’s University, Kingston, Ontario; University of Calgary, Calgary, Alberta; and the University of Alberta, Edmonton, Alberta, Canada.

The study “Clinical characteristics associated with increased risk of adverse events in patients presenting to the emergency department with exacerbation of chronic obstructive pulmonary disease: a prospective cohort study” was authored by Ian G. Stiell, Catherine M Clement, Shawn D. Aaron, Brian H. Rowe, Jeffrey J. Perry, Robert J. Brison, Lisa A. Calder, Eddy Lang, Bjug Borgundvaag, Alan J. Forster, George A. Wells.

It was funded by: Canadian Institutes of Health Research, University of Ottawa (University Health Research Chair and Clinical Research Chair), Government of Canada (Canada Research Chair), and The Ottawa Hospital Foundation.


Why did you create the Ottawa COPD Risk Scale? (Runs 1:09)
How does a physician use the Ottawa COPD Risk Scale? (Runs 0:42)

About the Ottawa Hospital Research Institute
The Ottawa Hospital Research Institute (OHRI) is the research arm of The Ottawa Hospital and is an affiliated institute of the University of Ottawa, closely associated with the university’s Faculties of Medicine and Health Sciences. OHRI includes more than 1,700 scientists, clinical investigators, graduate students, postdoctoral fellows and staff conducting research to improve the understanding, prevention, diagnosis and treatment of human disease.

Media contact
Paddy Moore
Communications and Public Relations
Ottawa Hospital Research Institute
613-737-8899 x 73687
613-323-5680 (cell)